What happens when you combine one of the healthiest vegetables around (cabbage) with one of the healthiest ways to prepare food (fermentation)? You get sauerkraut (which means "sour cabbage" in German), or fermented cabbage. This is one of the most popular and oldest ways to preserve cabbage, especially in Europe. But it shouldn't have to only be popular there. Why?
Fermentation & Human Health
While initially valued mostly for its ability to increase shelf life, recent research on the fermentation of foods shows that once a food is fermented, it provides health benefits beyond what the starting food materials provided. Yes, the fermentation process does more than just extend shelf life. It can enhance flavor, boost the nutritional value of foods, and can even reduce a food's toxicity. Where does this added nutrition come from? The fermentation process can transform some substances already found in the starter food and it can form new beneficial end-products, including living microorganisms that inhabit the digestive flora. Fermented foods are a hot topic for researchers today. The community of bacteria that reside in our gut is more complex than we ever knew. It can influence gut health and even help with disorders of the gut. However, the gut is linked to our immune system, our brain, and more. Therefore, we can expect these gut bacteria to influence the health of other parts of the body, too. Let's start with the gut, though. Certain probiotics Streptococcus thermophilus and Lactobacillus acidophilus have been shown to interact with cells of the intestinal wall to protect them from the effect of an E. coli bacterial infection. There was even evidence of these healthy bacteria enhancing the ability of the intestinal wall to act as a barrier against pathogenic bacterial infection. One study, though small in number of participants, showed that the probiotics in lacto-fermented sauerkraut was an effective addition to treatment for IBS patients. That's not all, though. A detailed review of scientific literature showed relevant studies on probiotic use for many medical conditions, including diarrhea, gastroenteritis, inflammatory bowel disease (Crohn's disease and ulcerative colitis), depressed immunity, infant allergies, failure-to-thrive, hyperlipidemia, liver diseases, H. pylori infections, genitourinary tract infections, and more. The Journal of Applied Microbiology reports in a 2006 paper that probiotics also play a role in the reduction of overall inflammation, enhancing nutrient absorption, preventing or reducing the symptoms of food allergies, improving hypertension, reducing cancer risk, lowering cholesterol, and more. Gut disorders are not the only thing probiotics can help with, though. More research is revealing the complex connection between the gut and brain - the gut-brain axis. While more investigation is still needed, research on the mental health benefits of fermented foods is emerging. In fact, the mental health field calls this treatment method psychobiotics - using bacteria-based treatment for mental health benefits. Even central nervous system disorders, such as Alzheimer's disease, are being looked into because of the connection observed between exposure to healthy bacteria and cognitive function. The benefits can even go beyond gut and brain health. Consider a study on the effect of probiotics on respiratory health. Probiotics have shown a positive, albeit modest, effect on preventing symptoms of the common cold. Many top-quality randomized-controlled trials have shown that probiotics can reduce the duration of acute respiratory tract illness in relatively healthy adults and children. I know what you're wondering. With all these health benefits, what about weight loss? Well, one study investigated the impact of probiotic supplementation on weight loss and weight maintenance in both obese men and women. They were given either a placebo or L. rhamnosus supplements for more than 24 weeks. Positive results were mainly seen in the women study subjects, who achieved significant sustainable weight loss with the daily probiotic supplementation as opposed to the placebo group.
Sauerkraut Nutrition Snapshot
So what's inside a serving of sauerkraut? Low in calorie density (only 16 calories per 2 T), sauerkraut provides 1 gram of fiber and 2.6 mg of vitamin C per 2 tablespoons. A 2003 study found as many as 28 different lactic acid bacteria strains in sauerkraut. Some of these strains include L. mesenteroides, L. plantarum, L. brevis, L. rhamnosus, and L. plantarum. These bacteria also produce enzymes that make it easier to digest the food than if it was unfermented.
Healthy Ways to Enjoy Sauerkraut
Typically, sauerkraut is associated with German bratwursts, New York style hot dogs, and Polish pierogis. A serving of sauerkraut is just as good atop other foods, such as whole grains, grilled burgers, salads and veggie dishes.
Small Batch Sauerkraut
One of the advantages of making a small quantity of homemade sauerkraut at a time is that smaller batches ferment quicker.
Ingredients
1 medium head of cabbage, variety of choice
2 tsp caraway seeds (if desired for extra flavor)
1.5-2 tsp sea salt (not iodized)
1/4 cup water (optional)
Directions
1. Slice or grate cabbage finely into thin ribbons (cut out the core). The more uniform the slices, the better for an even fermentation.
2. Add cabbage, caraway seeds and salt to large mixing bowl. Squeeze and massage cabba with fingers for about 5 minutes until cabbage releases some of its own juice.
3. Use fingers or spoon to stuff cabbage mixture tightly into a 2-quart container, such as a jar, with the liquid that it released until cabbage is submerged in the liquid. If not submerged by its own juice, you may add up to 1/4 cup of water to complete the liquid. (Idea: you can use one of the outer layer cabbage leaves to hold down the cabbage under the liquid).
4. Cover jar with a cloth and secure around mouth of jar with rubber band. Label contents and date.
5. Leave jar at room temperature (55° to 85° F).
6. Once a day for the first few days, open lid slowly just until gas escapes (if any), then close immediately. If necessary, continue to push down cabbage beneath the liquid it generates. It is normal to see cloudiness or some bubbling in the brine.
7. Allow cabbage to ferment for 3-10 days (give or take a few days depending on your set room temperature). You can start tasting it after 3 days or longer until it reaches a desired sourness. Refrigerate for up to 3 weeks or leave on counter if more sourness is desired.
References
Raak, C., Ostermann, T., Boehm, K., & Molsberger, F. (2014). Regular consumption of sauerkraut and its effect on human health: a bibliometric analysis. Global advances in health and medicine, 3(6), 12–18. https://doi.org/10.7453/gahmj.2014.038
Curr Opin Biotechnol. 2017 Apr;44:94-102. doi: 10.1016/j.copbio.2016.11.010. Epub 2016 Dec 18.
Swain MR, Anandharaj M, Ray RC, Rani RP. Fermented fruits and vegetables of Asia: a potential source of probiotics. Biotechnol Res Int. 2014;2014:250424.
US Department of Agriculture, Agricultural Research Service. USDA food composition databases. https://ndb.nal.usda.gov/ndb/. Updated April 2018. Accessed August 23, 2018
Lu Z, Breidt F, Plengvidhya V, Fleming HP. Bacteriophage ecology in commercial sauerkraut fermentations. Appl Environ Microbiol. 2003;69(6):3192-3202.
Fermented Foods: Sauerkraut - Today's Dietitian Magazine. (n.d.). Retrieved July 30, 2020, from https://www.todaysdietitian.com/newarchives/1118p12.shtml
Nielsen, E. S., , Garnås, E., , Jensen, K. J., , Hansen, L. H., , Olsen, P. S., , Ritz, C., , Krych, L., , & Nielsen, D. S., (2018). Lacto-fermented sauerkraut improves symptoms in IBS patients independent of product pasteurisation - a pilot study. Food & function, 9(10), 5323–5335. https://doi.org/10.1039/c8fo00968f
Sivamaruthi, B. S., Kesika, P., & Chaiyasut, C. (2018). Impact of Fermented Foods on Human Cognitive Function-A Review of Outcome of Clinical Trials. Scientia pharmaceutica, 86(2), 22. https://doi.org/10.3390/scipharm86020022
Brown, A. C., & Valiere, A. (2004). Probiotics and medical nutrition therapy. Nutrition in clinical care : an official publication of Tufts University, 7(2), 56–68.
Rios, A. C., Maurya, P. K., Pedrini, M., Zeni-Graiff, M., Asevedo, E., Mansur, R. B., Wieck, A., Grassi-Oliveira, R., McIntyre, R. S., Hayashi, M., & Brietzke, E. (2017). Microbiota abnormalities and the therapeutic potential of probiotics in the treatment of mood disorders. Reviews in the neurosciences, 28(7), 739–749. https://doi.org/10.1515/revneuro-2017-0001
Jiang, C., Li, G., Huang, P., Liu, Z., & Zhao, B. (2017). The Gut Microbiota and Alzheimer's Disease. Journal of Alzheimer's disease : JAD, 58(1), 1–15. https://doi.org/10.3233/JAD-161141
Viander B, Mäki M, Palva A. Impact of low salt concentration, salt quality on natural large-scale sauerkraut fermentation. Food Microbiology. 2003;20(4):391–395.
Wang C, Zhang X, Li D, Niu C, Yang Z. Study on the identification and resistant properties of Lactobacillus plantarum isolated from sauerkraut. Food Science and Technology. 2010;31:141–144
Yang Z, Li S, Zhang X, et al. Capsular and slime-polysaccharide production by Lactobacillus rhamnosus JAAS8 isolated from Chinese sauerkraut: potential application in fermented milk products. Journal of Bioscience and Bioengineering. 2010;110(1):53–57
Lei, Y. M., Nair, L., & Alegre, M. L. (2015). The interplay between the intestinal microbiota and the immune system. Clinics and research in hepatology and gastroenterology, 39(1), 9–19. https://doi.org/10.1016/j.clinre.2014.10.008
Resta-Lenert, S., & Barrett, K. E. (2003). Live probiotics protect intestinal epithelial cells from the effects of infection with enteroinvasive Escherichia coli (EIEC). Gut, 52(7), 988–997. https://doi.org/10.1136/gut.52.7.988
King, S., Glanville, J., Sanders, M. E., Fitzgerald, A., & Varley, D. (2014). Effectiveness of probiotics on the duration of illness in healthy children and adults who develop common acute respiratory infectious conditions: a systematic review and meta-analysis. The British journal of nutrition, 112(1), 41–54. https://doi.org/10.1017/S0007114514000075
Sanchez, M., Darimont, C., Drapeau, V., Emady-Azar, S., Lepage, M., Rezzonico, E., Ngom-Bru, C., Berger, B., Philippe, L., Ammon-Zuffrey, C., Leone, P., Chevrier, G., St-Amand, E., Marette, A., Doré, J., & Tremblay, A. (2014). Effect of Lactobacillus rhamnosus CGMCC1.3724 supplementation on weight loss and maintenance in obese men and women. The British journal of nutrition, 111(8), 1507–1519. https://doi.org/10.1017/S0007114513003875
Parvez, S., Malik, K., Ah Kang, S. and Kim, H.‐Y. (2006), Probiotics and their fermented food products are beneficial for health. Journal of Applied Microbiology, 100: 1171-1185. doi:10.1111/j.1365-2672.2006.02963.x